3,000 Feral Cats Killed to Protect Rare Australian Bilbies

Australia has a feral cat problem. Cats and other invasive predators have driven dozens of the country's native bird, reptile and small mammal species into extinction, and continue to threaten several others. So many feral felines roam the country that the government often traps, shoots or poisons the animals in order to control populations.

Most recently 3,000 feral cats were shot during a 16-day period in Queensland to keep them away from a 29-square-kilometer sanctuary designed to protect the endangered greater bilby (Macrotis lagotis), a defenseless, one-kilogram marsupial that looks like a cross between a mouse and a rabbit, although it is related to neither. Greater bilbies, the last surviving species of their genus, could once be found across most of Australia. Predation by invasive foxes and feral cats took a deadly toll on the species, which also encountered new competition for food and habitat from invasive rabbits. Today only about 600 to 700 remain in the wild. The only other Macrotis species, the lesser bilby, was driven into extinction in the 1950s by the same invasive fauna.

To help save the greater bilbies from the same fate, the Save the Bilby Fund built the Queensland sanctuary back in 2001. The initial construction trapped a large number of predators inside the fence—something they expected to happen—so the organization spent the next few years clearing them out to ensure that the new habitat would be safe, although numerous predators remained outside its gates. The first four bilbies were placed in the sanctuary in 2005, where they quickly started breeding. Within a few years that number had increased to more than 100.

Unfortunately, the sanctuary is located in a relatively remote region of Currawinya National Park. Flooding in the park not only makes the sanctuary occasionally unreachable by humans, it also apparently damaged the fence last June, allowing several cats to make their way into the enclosure, with devastating results. "We estimated we could have had around 150 newborn bilbies inside that fence, and [the cats have] cleared the lot out," Frank Manthey, co-founder of the Save the Bilby Fund, told the Australian network news show 7.30.

The fence has since been repaired, but Manthey says the surrounding countryside is still besieged by feral cats and has appealed to the government for help in reducing their numbers. Feral cat populations have actually risen in the past two years, an unintended side effect of government efforts to control dingo populations. Dingoes, which compete with cats and other predators for food, have been poisoned to protect agricultural sheep, but Griffith University researcher Jean-Marc Hero told The Australian last September that this approach gave cats and foxes a chance to fill the ecological gap the dingoes left behind.

And if the losses at the sanctuary weren't bad enough, the worldwide economic crisis has also had an impact on bilbies. The Save the Bilby Fund lost one of its major sponsors about the same time that the sanctuary fence was breached when the chocolate retailer Darrell Lea went belly-up. Darrell Lea raised about $50,000 for the fund each year by selling candy bilbies instead of the traditional chocolate rabbits.

Although it is unclear when the Queensland sanctuary will be restocked with bilbies, other efforts continue to protect the species. The Australian Wildlife Conservancy operates a similar, 8,000-hectare fenced-in property in New South Wales that contains bilbies as well as five other threatened species. That site is patrolled every other day to make sure its fence remains secure. Elsewhere, the Dreamworld theme park on Queensland's Gold Coast recently celebrated the first captive birth of triplet bilbies, part of a breeding effort that could eventually be used to boost wild populations.

That's not the only good news. Manthey told 7.30 that he has found a new chocolate manufacturer, Melbourne's Fyna Foods, which has rushed new chocolate bilbies to their stores just in time for this year's Easter season. Fyna made an initial $10,000 donation to the bilby fund at the beginning of March. That still leaves the organization well behind its fund-raising needs—but it's a start.

Twice a week, John Platt shines a light on endangered species from all over the globe, exploring not just why they are dying out but also what's being done to rescue them from oblivion.
Follow on Twitter @johnrplatt

The views expressed are those of the author and are not necessarily those of Scientific American.

Share this Article:

Comments

Welcome to the Scientific American Blog Network, a forum for a diverse and independent set of voices to share news and opinions and discuss issues related to science. For more information see our About page and Guidelines....more